Twisting head



HADWICH TWISTING H Filed Jan. 25, 1952 .zmewm 71 A DIM/(1 a ll)" w vvmlmwm In: 019M69 TWISTING HEAD Fritz Hadwich, Bremen Farge, Germany, assignor to Schiess Aktiengesellscliaft, Dusseldorf-Oberkassel, Germany Application January 23, 1952, Serial No. 267 ,750

(Ilaims priority, application Germany January 24, 1951 Claims. (Cl. 57--51.4)

One of the main causes why twisting heads for spinning and twisting frames have not been fully utilised in practice is that the roving readily laps around rapidly rotating delivery rollers. This results in interruptions as, with the known constructions, the twisting heads have then to be opened and even be partly removed from the frame. In addition, the known twisting heads are subject to the great danger of being soiled by fibrous fiuif and the impurities contained in the roving, the removal of which necessitated from time to time stopping the frame and perhaps opening the twisting heads. These conditions conflict with the requirement for continuous operation.

The present invention is based on the realization that stripping edges must be provided adjacent the delivery rollers of the twisting heads. However, on account of the special conditions pertaining to twisting heads, the rectilinear stripping edges as heretofore known on other rollers would not be successful, because the delivery opening or the delivery duct for the twisted material must, as far as possible, be of circular cross-section. When straight stripping edges are used, they form with the cylindrical delivery duct, dead spaces behind the delivery rollers which become filled with fibre fiuff and interfere with the operation of the twisting head.

According to the present invention, the parts of the rollers disposed beyond the nip of the rollers are enclosed with small clearance by the delivery roller housing with cylindrical surfaces in such manner that those surfaces, together with the delivery duct commencing directly at the rollers, form a kind of stripping edge at the rollers for the yarn. The delivery duct with this construction therefore proceeds directly from the delivery rollers, and its upper surface closely conforms to the cylindrical surface of the rollers, so that the yarn issuing from the rollers meets only the inlet opening of the duct and consequently can only pass into that opening. The clearance between the upper surface of the delivery opening and the rollers which is necessary in order to permit rotation of the delivery rollers without friction, is kept so small that the material cannot pass through in any case, thereby excluding the possibility of lapping round the rollers.

On the other hand, however, small particles of fibre and dirt can pass through the clearance space. Accordingly, another feature of the invention consists in the arrangement of lateral passages in the delivery roller housing which adjoin the cylindrical surfaces or the clearance space and lead outwardly. Fibrous fluff and particles of dust are thrown outwards through these passages due to centrifugal force, whereby a continuous automatic cleaning of the twisting head is achieved.

Further details of the invention and the method of operation thereof will be apparent from the following description of one example of construction which is illustrated in the accompanying drawing, in which:

Figure 1 is a vertical section through a twisting head;

2,752,748 Patented July 3, 1 956 Figure 2 is a perspective view of the bottom part of the delivery roller housing and one delivery roller.

The roller housing 1 of the twisting head shown in Figure 1 is made in two parts. The upper part provides a roving feed conductor 2 on which runs a helical gear 3 having a toothed annulus 4 which meshes with pinions 5 arranged on opposite sides of the delivery rollers so that the latter rotate in opposite directions. The gear 3 is driven by a gear 7 from the upper driving shaft. The lower part of the roller housing 1 is formed with lateral helical teeth 8 which mesh with a helical gear 9 on the lower driving shaft.

The lower part of the roller housing 1 has a bush-like extension 10 mounted in the external housing 11 secured to the frame. The extension 10 provides a vertical delivery or outlet duct 12 of circular cross-section through which the yarn leaves the spinning head. This outlet duct 12 flares downwardly.

The lower part of the roller housing 1 has cylindrical guide surfaces 13 which extend with small clearance around those parts of the delivery rollers 6 which are beyond the nip of the rollers so that, as shown in Figure l, something less than a quarter of the total periphery of the delivery rollers is enclosed. The delivery duct 12 and the guide surfaces 13 define, directly below the delivery rollers, shipping edges 14 which, being the intersection of two cylinders, are three-dimensional curves.

Between the guide surfaces 13 are lateral passages 15 leading to the outside of the roller housing. The bottoms of these passages are stepped downwards from the guide surfaces 13, as indicated at 16.

For supporting the delivery rollers, webs 17 are provided in the roller housing which are disposed one on each side of the guide surfaces 13 and the passages 15 and provide side walls for those passages. The spacing of the webs 17 from one another is somewhat greater than the diameter of the delivery duct 12 and thus determines the width of the guide surfaces 13, as can be seen in Figure 2. Over their central portion Where the delivery rollers 6 are mounted, the webs 17 extend parallel to one another, but on either side of that portion, they diverge from one another. The driving gears 5 of the delivery rollers 6 are enclosed in the spaces between the webs 1.7 and the outside wall of the housing 1.

From the arrangement which has been described, it is apparent that because of the provision of the guide surfaces 13, the delivery duct 12 conforms closely to the delivery rollers where the yarn emerges from the nip of the rollers. There are no openings or dead spaces except for the small clearance which must exist between the guide surfaces 13 and the delivery rollers to permit free rotation of the latter. The clearance may be made very small, but, with flexible delivery rollers, it should be such that even on distortion of the delivery rollers, caused by impurities, by the handling of rovings of different thicknesses, etc., satisfactory operation is ensured. Under normal conditions, a clearance of about 0.02 millimetre is appropriate.

It is now no longer possible for the roving to lap on the rollers, since the yarn, after passing the delivery rollers, can only pass into the delivery duct 12. On the other hand, fibrous fluff and small particles of dirt can pass through the clearance space. It is not absolutely necessary for this passage to take place continuously. In practical working, the procedure is rather that initially, fibre particles and the like settle in the clearance space and it is only after a certain quantity has collected that, on account of the increasing weight, they are forced outwards by centrifugal force and expelled. This constant accumulation of fluff in the clearance space is not a disadvantage, but is quite in accordance with the invention, since by this means there is constantly provided a kind of cushion-likesealing of the clearance space, so 'thatwhen afresh end of roving is fed, there is :no possibility of the latter being able to pass through the clearance space. The .cons'truc'tion inaccordance with the invention therefore -com pletely excludes lapping of the roving about the delivery rollers.

The close positioning of the delivery duct and the delivery rollers is optional. In the example which is illustrated, it is assumed that all parts, such as the guides 13, the delivery duct '12, the passages 14 and the like are made in one piece with the roller housing 1. In this .case, the roller housing can usefully 'be manufactured of a mouldahle material thus avoiding the necessity for milling the guide surfaces 13 and the like. .However, it is obvious that the individual parts may be made independently: for example, it is poss'ibleto make the delivery duct 12 as a tube'w'hich is fitted 'in the roller housing. In that case, for the close juxtaposition ofthe small delivery 'tube to the delivery rollers, the guide surfaces may be formed on the tribe itself, its upper end being suitably shaped by milling .or the like. It is .then possible to regulate .the size of the clearance space within certain limits by adjustment of'the tube. In the example described, the passages 15 are arranged in the upper and lower part of the roller housing. It is, however, sutficient to provide them in only one of the two parts of the housing.

I claim:

1. A twisting head for spinning and twisting frames comprising-a plurality of delivery rollers arranged to form a hip, means for rotating said rollers about their axes, a housing .in which said rollers are mounted and which is revolu'ble about an axis at right angles to the nipping line, and an outlet duct in said housing for receiving twisted material passing through said n'ip, said outlet duct having bounding surfaces forming stripping .edges conforming to the surface of said rollers and disposed very close to but venting the material from lapping around the rollers, said housing having lateral passages which communicate with said outlet duct through the clearance between said surfaces and said rollers, dirt particles and fluff being discharged through said clearance and lateral passages.

2. A twisting head as claimed in claim 1 in which the bottom bounding sin-face ofsaid lateralpassages is stepped downwards from the lowest point in said bounding surfaces.

3. A twisting head as claimed in claim '1 in which said housing has a pair of webs adapted to support said rollers and defining between them said lateral passages.

4.. A twisting head according to claim 3 in which said We'bs are spaced apart a distance greater than the distance across the outlet duct.

5. A twisting head as claimed in claim 1 in which said housing has a pair of webs adapted to support said rollers and defining between .them .said lateral passages, said webs extending-parallel .to-each other over their central portions and .di-verg-ing laterally iromeach otherover their end portions.

References Gited in the file of this patent UNITlED STATES PATENTS 28,161 Crowell May 8, 1860 31,031 Plummer Jan. 1, 1861 135,338 Howard Jan. 28,, 1873 337,015 Pease Mar. 2, 1886 682,245 Dreman Sept. 10, 1901 1,746,433 Leonard Feb. 11, 1930 2,522,332 Abbott Sept. 12, 1950 FOREIGN PATENTS 5,134 Great Britain 1881 28,325 Great Britain 1907 574,360 France Mar. 28, .1924 

